Special notes for using a devicenet system, Special notes for using a devicenet, System -3 – KEYENCE LK-CC100/DN100 User Manual

Page 39

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3-3

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3 Connecting to DeviceNet

Special notes for using a DeviceNet system

Take note of the following when using the LK-DN100 in a DeviceNet network.

• DeviceNet supports up to 64 connected devices. This includes the master, slaves, and

configurable devices.

• The maximum total length of the entire DeviceNet network is 500 m (at 125 kbps). Refer

to the following table for the relation between communication speed and maximum

cable length.

• Connect the LK-DN100 using the dedicated 5-wire cable for DeviceNet. KEYENCE will

not guarantee performance if any other cable is used.

• Always connect a terminator (121 ohms, 1% 1/4W metal-film resistor) at both ends of the

trunk line.

• Do not connect any non-DeviceNet components along communication line. Otherwise,

signal reflection and other problems may cause communication failures.

• Only one point on the network must be ground to a ground resistance of 100 ohms or

less. If a ground resistance of 100 ohms or less is not available, do not connect the FG

to the V- on the communication power supply to avoid problems caused by noise.

• Do not connect the shield to multiple locations on the network.

Precautions on DeviceNet settings

• Set the LK-DN100 parameters according to the DeviceNet master unit using the Node

Address setting switch and Data Rate setting switch.

• Refer to the manual for the DeviceNet master unit for details on how to set it.

When wiring the LK-DN100, use connectors, cables, T-splitters, and terminators that comply with
published ODVA (Open DeviceNet Vendor Association, Inc.) specifications.

Type of
cable

Communication
speed

Max. length
of network

Branch
lengths

Total branch
length

Current
capacity

Thick cable

500 kbit/s

100 m

6 m

36 m

8 A

250 kbit/s

250 m

78 m

125 kbit/s

500 m

156 m

Thin cable

500 kbit/s

100 m

36 m

3 A

250 kbit/s

100 m

78 m

125 kbit/s

100 m

156 m

NOTE

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